Internal combustion engine



DCC. 12, 1939. 5 COA-TES 2,183,116

INTERNAL COMBUSTI 0N ENGINE A'TT Ey Dec. 12, 1939.

J. s. coATEs n INTERNAL COMBUSTION EGINE Filed April 25, 1938 v 2 Sheets-Sheet 2 :5., R E0 W( 5 M efvl d ATT Patented Dec. 1 2, 1939 muicanino conmnsrron' ENGINE y Joseph S. uCoates, Goshen, Y. Application April 25, 193s, serial No; 204,241 y comme (ci. we m n This invention relates particularly to internal combustion engines in which ignition of the fuel occurs every time the piston approximately reaches the end' of theoutward orupward stroke,

erroneously called two cycle engines, but the improvements also are applicable to two' stroke Diesel engines using the injectionl method of fuel and some of the improvements may be apl pliedy to other internal combustionr engines. 'io Among numerous objects, one of great im'- portancevis to produce a pure fuel, stored under pressure and held in. storage while combustion pressure has driven the piston almost the entire length of its stroke and the spent gases have 25 mixture which is slower to ignite, a factwhich` is made evident by the back-refto thecarburetor, common to the starting' o-f a cold engine, but which is instantly checked by pulling the choke throttle andy enriching the mixture.l

39 Another object is to provide foreach powerv cylinder' of an engine, a storagereservoir for fuel under-pressure and in sufcient volume to insure filling of the cylinder at a pressure'higher than atmosphere. l'

Another object is to utilize in the most eiiicient manner, the evaporation of the fuel as a means to coolv the piston and simultaneously to utilize the heat or" the piston to complete the vaporization of the fuel which no carburetor can comtu; plete. y Y l y Another object is to provide in advance of its use, a volume of fuel, under pressure stored in a reservoir attached tothe cylinder which pressure automatically increases with the increase 4;; in engine speed, thereby largely through the increased pressure compensate for the shortened period of time, at high speeds, during which time fuel can pass into the cylinder from the reservoir 5;, than has heretofore been v feasible.

Another object isto eliminate parts and simplify the engine and to reduce the weight and tlie'cost per horsepower.

Additional objects, advantages andfeatures of invention will be apparent from the following 5 description considered in' conjunction'with the accompanying drawinga'wherein y Figure l'is 'a' vertical section throughy the engine.A

Figure 2 isa cross section on .the line 2-2 of j() Figure 1. y Y

yFigure 3 is a plan view of a packing ring ernl ployed in the engine.`

VFigure 4 is a fragmentary cross section thereof.

VIn carrying out the invention, I provide a la crank case lil of any approved construction upon which there is mounted tandem cylinders ll and i2, each of which is cored as at I3', to provide passage ofa cooling liquid, as is customary.

The cylinder li is of greater diameter than 2UY the cylinder l2,- and the pistonl i3 therefore, has an'V enlarged base it, complemental'to the cylinand a reducedportion l5 is slidably ender it gage'd in the cylinder if. Thus, a chamber I6 is provided in the cylinder H and into the upper 25,

endthereof a porty il is. formed. Diametrically opposite, a port i8 is provided, establishing connectionwith a carburetor (not shown) by way of a rotary valve i9 and pipe 2Q', which will be described hereinafter in detail. 39

The cylinder i2 has a laterally extended port 25 in registry with a port '21 formed in the valve cage 2l, and with the former port there is secured a -pressu're'fuel rreservoir 23,' the latter extending downwardlyvparallel to the cylinders il and lzand has an opening 29 for registry 45 with 'the port ll of the cylinder H.

Aty the side opposite the port ll, the reservoir has a threadedopening toreceive 'a valve guide The guide comprises a sleeve 3i receiving the stern 32 of a poppet valve iQadapted to seat' 50 ,upon-l and control passagev of fuel through the port` ll, the valve being held closed by'a spring 34. In the bottom Aof the reservoir 28 there is securedafball valve 35, which inthe present instance is "shown as mounted in a-cage'36,`the 55'.

lower end of which is interiorly threaded to receive a screw plug 31. A helical spring 38 is interposed between the upper end of the plug and the ball 35 to hold the ball against its seat. A cup 39 is threadedly engaged upon the lower end of the cage 3B, and has a removable plug 49 in the base thereof aligned with the plug 31 in order that the plug'3'I may be adjusted to vary the tension of the spring 38, upon removal of the plug 40 A pipe 4| opens upon the cup 39 and leads to the main fuel tank 39 and by reason of this connection condensed Vapor which may occur is conducted back to its original source.

The cylinders I I and I 2 are formed as separate members suitably bolted together in end to end relation, and in the base of the cylinder I2 an annular recess 42 is formed, seating a constriction ring 43, which will now be described, reference being had to Figures 3 and 4. The ring 43 is of a diameter slidably receiving the piston I5 therethrough and comprises a pair of superposed ring members 44, the abutting face edges being grooved peripherally as at 45 to receive and seat a garter spring 46. The ring members 44 have their split portions 4T positioned diametrically opposite each other, and the contacting faces of the rings are provided with a plurality of radially spaced grooves 48, extending from the inner to the outer peripheries of the members, these grooves serving as oil passages feeding oil to the rings and piston by way of the oil duct 49.

The ring 43 is preferably held in place by means of a plate secured between the abutting upper and lower ends of the cylinders I2 and II, and one or both 0f the cylinders may be recessed to accommodate the plate.

The cylinder I2 adjacent its base is provided with a plurality of exhaust ports 5I extending half way or more around the cyilnder circumferentially, the ports being in communication with a semi-annular passage 52, for discharge into an exhaust pipe 53. Obviously, for an engine automatically exhausting spent gases at the bottom of the cylinder, it is absolutely essential to provide a large exhaust area to obtain complete scavenging of gases, and the construction described greatly increases the exhaust area, as compared with the usual plan of utilizing only part of a side of a cylinder.

The construction and operation of the valve I9 will now be dealt with, reference being made to Figures 1 and 2. As may be seen the valve is of the rotary plug type, having a transverse port 54, the valve being suitably housed in a cage 55, the latter being bolted to the side of the cylinder II so that the port 54 will register with the port I8, at times. The Valve I9 includes a shaft 56 upon which there is keyed a sprocket wheel 5l adapted to be driven by a suitable chain. The shaft will be of a length to extend to all cylinders which the engine may comprise and preferably between each two cylinders there is provided a universal joint 58, diagrammatically shown.

The operation The operation of the engine with carburetor throttle wide open is best described by assuming the combustion space in the top of the power cylinder filled with compressed fuel, the piston being very nearly at top center and fuel storage reservoir 28 filled at maximum pressure. Ignition takes place by spark plug 59 and the piston descends on its power stroke during which movement the enlarged base I4 of the piston in the lower and larger cylinder is drawing fuel, by

suction, from the carburetor through the rotary valve I9, which opened when the piston started to descend. When the top of the piston has descended to a position about three-eighths of an inch or more below the top of the exhaust ports 5I, the overhead valve 23 opens to admit fuel from the fuel reservoir into the power cylinder, thus the exhaust gases start going out before the fresh fuel starts coming in. During the further travel of the piston to bottom center and its upward movement so that the exhaust ports are closed the spent gases have entirely passed out of the exhaust ports and during the time that the piston was moving as just described the valve 23 was open and is about to close. Simultaneously, the step of the piston in the lower cylinder having reached bottom center and risen slightly the valve I9 from the carburetor has closed and both cylinders are lled with fuel. The further rise of the piston to top center results in highly comi.

pressing the fuel in the upper cylinder I2, simultaneously forcing the fuel in the lower cylinder II, through lthe Valve 32 into the storage reservoir 28, thereby restoring the pressure therein,

which had been depleted when the overhead valve 23 was previously opened. That completes the operation of the two strokes of the piston, one stroke in every two being a power stroke. The overhead valve 23 is not opened until the piston has practically reached bottom center, hence the fuel is held in storage during the period of time required for the piston I5 to move practically one stroke, or at least 35% thereof.

I assert that my objects as heretofore set forth have been attained, which an analysis of the exhaust gases of this engine taken by a responsible laboratory clearly shows. This engine exists and is in operation. The analysis of the exhaust shows 98.5% of the fuel burned, .003% of carbon monoxide, compared to a test taken the same day of a standard make of a four cycle engine, which showed 78% of the fuel burned, 4.5% of carbon monoxide.

I claim:

l. In an internal combustion engine of the two-stroke type, a pair of tandem cylinders, one of the cylinders having a diameter greater than the other, a piston, said piston having portions complemental to respective cylinders, a fuel in- .f

take port opening upon the larger cylinder, valve means for controlling passage of fuel to the cylinder, a fuel reservoir, the larger cylinder having a port opening upon the reservoir, a valve constructed for admitting fuel under pressure 1 from the cylinder to the reservoir, the reservoir having communication with an upper portion of the smaller cylinder, a Valved by-pass associated with the reservoir for return of condensed vapors to its original source, a valve cage in the smaller cylinder, said cage having a port in communication with the reservoir and further having a valve seat opening upon the cylinders, a poppet valve reciprocably mounted in the cage, a cam operable at engine speed for reciprocating the valve, said smaller cylinder having a plurality of exhaust ports adjacent the base of the cylinder, said ports being spaced circumferentially for half way or more of the cylinder, and an exhaust chamber complemental to the exhaust ports.

2. In an internal combustion engine of the two-stroke type, a pair of tandem cylinders, one of the cylinders having a diameter greater than the other, a piston, said piston having portions complemental to respective cylinders, a fuel inreservoir having communication with an upperl portion of the smaller cylinder, a valved by-pass associated with the reservoir for return of condensed vapors to its original'source, a valve cage in the smaller cylinder, said cage having a port in communication with the reservoir and furtherV having a valve seat opening upon the cylinders, a valve reciprocably mounted in the cage, means operable at engine speeds for reciprocating the valve, and exhaust ports at the base ofr the smaller cylinder.

JOSEPH S. COATES. 

